It is desirable from a marketing standpoint to increase the storage or shelf life of various comestible products. This is accomplished by employing various sterilization processes. Heretofore, sterilization of thermoplastic coated, liquid carryng paperboard containers has typically been acomplished on the forming, filling and sealing machine at a location between the station where the bottom formed container is stripped from an indexing mandrel and a station downstream thereof where the container is filled with a liquid, such as milk or juice. Such an arrangement is shown and described in Lisiecki U.S. Pat. No. 3,566,575, issued on Mar. 2, 1971.